1. Technical Field
The present invention relates to a non-contact position sensor that detects a position of an object with magnetic field.
2. Background Art
FIG. 7 is a perspective view of conventional non-contact position sensor 501 described in Patent Document 1. Magnet 1 is magnetized in its thickness direction. Magnetic body 2 is made of permalloy and has an isosceles triangle shape having different widths at positions along a longitudinal direction. Magnetic body 2 is provided on an upper surface of magnet 1. Magnet 1 is provided on an upper surface of shaft 3. Shaft 3 has a side surface having groove 4 provided therein. Projection 6 is provided on an inner side surface of slider 5. While projection 6 is engaged with groove 4 of shaft 3, slider 5 slides in longitudinal direction 501A of shaft 3. Magnetoelectric converter 7 is provided on an upper surface of slider 5 and detects a magnetic field changing depending on the width of magnetic body 2. Magnetoelectric converter 7 is connected to lead wire 8. Lead wire 8 is connected to an external device, such as a computer.
An operation of conventional non-contact position sensor 501 will be described below.
Upon shaft 3 being displaced in longitudinal direction 501A with respect to magnetoelectric converter 7, magnetic body 2 having the isosceles triangle shape is displaced and the width of magnetic body 2 facing magnetoelectric converter 7 changes, accordingly changing a magnetic field crossing magnetoelectric converter 7. The change of the magnetic field is converted by magnetoelectric converter 7 to a change of a voltage. This change of the voltage is output via lead wire 8 to the external device, thus allowing the external device to detect the displacement of shaft 3.
Conventional position sensor 501 includes magnetic body 2 having an intricate shape, such as the isosceles triangle shape, and made of permalloy, thus being prevented from being manufactured easily.    Patent Document 1: JP5-264326A